This is where one PC connects to the internet (DSL, ISDN, Cable, DUN, ...etc.) then anyone on the LAN can connect through the connected PC. Basically the functions of a router and gateway. The Connected PC performs DHCP and can act as the firewall for the LAN. MTU, MSS, RWIN settings may be different through the connection.

First go to the Network and Dialup connection to the internet and right click to Properties.

Click on the sharing tab and Enable sharing and on demand dialing. The dialup on the sharing PC will activate (if not already connected to the internet) when someone tries to use their browser on the LAN. Note that on the Dialup that TCP/IP is not bound to any services or client. On the LAN PCs, for security, do not use or bind TCP/IP to any services or client, do not do any LAN networking with the TCP/IP protocol. Use NETBEUI protocol.

Clicking on sharing enables DHCP, performs NAT (Network Address Translation), and modifies the LAN Ethernet board setting for TCP/IP IP address (192.168.0.1)and subnet mask (255.255.255.0).

Click on the Advanced button and you should see on the DNS tab that all is selected except Append these DNS suffixes. The WINS tab has Use NetBIOS setting from DHCP server is selected. On the Options tab you will see that there are settings for TCP/IP filtering (firewall type work) and IP Security.

That is all the settings for the sharing PC. There are many Security settings for Internet networking in Administration, Computer Management.

Set up the Ethernet board TCP/IP to obtain an IP address automatically (in this case the IP address was 192.168.0.155).

On the Gateway tab, enter the IP address of the sharing PC which is always 192.168.0.1, the DHCP host. On the WINS tab enable Use DHCP for WINS resolution. On the Bindings tab, nothing (client or service) should be selected for security purposes.

On the DNS tab, you need to enable DNS, select a host name (I just put in "1", I don't know why it is needed). Enter the DNS of the shared PC internet connection. If you do not use a DNS, you can still access the internet by IP address, if you know it. If you had been using a personal firewall on the sharing PC, you will need to upgrade to a Network firewall, or disable the firewall altogether.